This invention relates to an electronic musical instrument having switches for selecting a tone control function such as a tone color.
In an electronic musical instrument generally, separate tone color selection switches are provided with respect to respective selectable tone colors. Similarly, separate selection switches are provided for various tone effects and other functions. The number of tone colors, effects and other tone control functions selectable in the electronic musical instrument therefore is limited to the number of selection switches provided on an operation panel. If it is desired, to increase the number of the tone color functions, the number of the selection switches must be increased accordingly with resulting increase in the cost and difficulties in securing space for disposing switches and in ensuring a sufficient operability. When, for example, the tone color is to be changed during the performance of the keyboard, there is likelihood that the player cannot find a desired tone color selection switch readily or, if he can find it readily, he erroneously operates a wrong switch by mistake, if there are too many switches.
Besides, in an electronic musical instrument, there are provided one or more tone groups consisting of plural tone colors, effects or other tone control functions which tone groups are grouped in accordance with some common factor such as the kind of keyboard or the tone generation system and various tone control functions such as tone colors and effects can be independently selected tone group by tone group. Accordingly, separate selection means must be provided for respective tone groups even for the same function (e.g. the same tone color) so that the same problem as described above arises as a result of increase in the number of selection switches.
For improving operability of tone color selection switches during the performance of the keyboard, it has recently been proposed to select a tone color by providing a predetermined small number of switches as switches to be operated during the performance, selecting some tone colors from among numerous selectable tone colors and prestoring the selected tone colors in correspondence to these small number of switches, and selectively operating these switches during the performance. This method however has the disadvantage that it cannot cope with a situation in which the player desired to select, during the performance of the keyboard, a tone color instantly from among a relatively large number of switches which correspond one to one to a relatively large number of tone colors. Such selection operation can be made if a group of switches consisting of a relatively large number of selection switches which correspond one to one to a relatively large number of tone colors are provided additionally with the predetermined small number of switches. This however will apparently result in increase in the total number of switches.